<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
</head>
<body>
    <form action="/user/login" method="post">
        <!--这里必须叫username和password,在UsernamePasswordAuthenticationFilter过滤器中可发现
        还必须是post请求-->
        <input placeholder="用户名" name="username"><br>
        <input placeholder="密码" name="password"><br>
        <input type="submit" value="login">
    </form>
</body>
</html>